The present invention relates in general to the cooling of and the heat transfer from cylinder liners which are associated with internal combustion engines. More specifically the present invention relates to the use of a turbulator in the area of the cooling jacket which is disposed between the block and the cylinder liner.
In the field of cylinder liner design, cooling of the cylinder liner and in particular uniform cooling of the liner is an important consideration. Non uniformity in cylinder liner cooling results in localized hot spots which will adversely affect ring life and create lubricant deposit formation. Another consequence of nonuniformities in cylinder liner cooling is thermal distortion. In turn, thermal distortion results in increased oil consumption.
It has been found by enhancing the heat transfer coefficient around the cylinder liner that the cooling nonuniformities can be measurably reduced. In turn, one way to enhance the heat transfer coefficient is to create flow turbulence in the cooling fluid. More specifically, turbulence in the cooling fluid in the cooling jacket area will enhance the heat transfer coefficient throughout the cooling jacket and reduce temperature nonuniformities. An additional advantage is that enhanced heat transfer coefficients may be obtained while simultaneously reducing the coolant flow considerably. This allows the designer to use a smaller water pump, requiring lower horsepower and improving fuel consumption.
Over the years various efforts have been made to control or modify the cooling of internal combustion engines and in particular the cooling of cylinders and cylinder liners. The following patents are believed to be representative of such earlier efforts:
______________________________________ Patent No. Patentee Issue Date ______________________________________ 2,085,810 Ljungstrom July 6, 1937 1,231,904 Junkers July 3, 1917 1,410,319 Junkers Mar. 21, 1922 1,904,459 Hefti Apr. 18, 1933 2,001,854 Shoemaker et al. May 21, 1935 4,667,635 Lichtblau May 26, 1987 ______________________________________
In addition to what these six listed patents may disclose, some engine manufacturers have elected to machine scrolling or other relief around the cylinder liner perimeter surface in an attempt to enhance the heat transfer coefficient. Still other manufacturers have elected to cast fins around the cylinder liner perimeter. While these methods may provide some degree of enhancement, they represent extremely costly measures which then become prohibitive for many manufacturers in a price-competitive market.
The present invention is easy to fabricate and install and is far less expensive than competitive designs. The present invention significantly improves liner temperature distribution. The material options for the present invention, its adaptability and its variety of assembly options make the present invention well suited for a wide range of liner sizes and configurations.